Update screenshots

Author: developersu

README.md

@@ -8,7 +8,9 @@ Please note: You will need USB-OTG cable. Otherwise, you'll be charging phone.
 
 Sometimes I add new posts about this project [on my home page](https://developersu.blogspot.com/search/label/NS-USBloader).
 
-<img src="fastlane/metadata/android/en-US/phoneScreenshots/Screenshot_1.png" alt="screenshot-1" width="400"/>  <img src="fastlane/metadata/android/en-US/phoneScreenshots/Screenshot_2.png" alt="screenshot-2" width="400"/>
+<img src="fastlane/metadata/android/en-US/images/featureGraphic.png" alt="Application logo" width="500"/>
+
+<img src="fastlane/metadata/android/en-US/phoneScreenshots/Screenshot_1.png" alt="screenshot-1" width="250"/>  <img src="fastlane/metadata/android/en-US/phoneScreenshots/Screenshot_2.png" alt="screenshot-2" width="250"/>
 
 #### License